<html>
<head><meta charset="utf-8"><title>polonius, universes, and subregions · t-compiler/wg-nll · Zulip Chat Archive</title></head>
<h2>Stream: <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/index.html">t-compiler/wg-nll</a></h2>
<h3>Topic: <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html">polonius, universes, and subregions</a></h3>

<hr>

<base href="https://rust-lang.zulipchat.com">

<head><link href="https://rust-lang.github.io/zulip_archive/style.css" rel="stylesheet"></head>

<a name="154758101"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758101" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758101">(Jan 09 2019 at 21:12)</a>:</h4>
<p>BTW <span class="user-mention" data-user-id="116113">@lqd</span> I've been thinking about this on and off and it'd maybe be useful to bounce some things off of someone. Interestingly, I think I wound up going back to the "pure subset"-based version, though for efficiency I suspect we'll want a sort of hybrid model. It's a bit out of cache now though. I'm trying to decide how best to proceed. I feel like I've been sitting on said posts too long though.</p>



<a name="154758116"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758116" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758116">(Jan 09 2019 at 21:13)</a>:</h4>
<p>Well, maybe I'll make another effort to finish them off just to have some starting point for discussion.</p>



<a name="154758171"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758171" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758171">(Jan 09 2019 at 21:13)</a>:</h4>
<p>oh interesting</p>



<a name="154758319"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758319" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758319">(Jan 09 2019 at 21:15)</a>:</h4>
<p>is this something where we can prototype some ideas maybe ? (but I feel you've been doing that)</p>



<a name="154758539"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758539" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758539">(Jan 09 2019 at 21:18)</a>:</h4>
<p>(I was myself using the posts, trying out the rules, etc to start familiarizing myself with these new (to me) problems)</p>



<a name="154758856"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758856" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758856">(Jan 09 2019 at 21:22)</a>:</h4>
<p>yeah, probably</p>



<a name="154758862"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758862" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758862">(Jan 09 2019 at 21:22)</a>:</h4>
<p>I think I was "basically satisfied" with the rules, iirc, but some parts felt less elegant than I might liek</p>



<a name="154758872"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758872" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758872">(Jan 09 2019 at 21:23)</a>:</h4>
<p>and I kind of couldn't decide which was better</p>



<a name="154758879"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758879" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758879">(Jan 09 2019 at 21:23)</a>:</h4>
<p>but yeah I have to try and remember what I was concerned about</p>



<a name="154758897"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758897" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758897">(Jan 09 2019 at 21:23)</a>:</h4>
<p>I remember — among other things — rediscovering for the umpteenth time why some of the polonius rules are the way they are, which got me to thinking that it'd be nice to do a blog post on some of the more subtle points</p>



<a name="154758954"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758954" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758954">(Jan 09 2019 at 21:24)</a>:</h4>
<p>(notably the interaction of the subset/liveness/etc)</p>



<a name="154758959"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758959" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758959">(Jan 09 2019 at 21:24)</a>:</h4>
<p>but also: we really should do some a renaming PR</p>



<a name="154758963"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758963" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758963">(Jan 09 2019 at 21:24)</a>:</h4>
<p>I want to rename <code>requires</code> to <code>contains</code>, in particular</p>



<a name="154758973"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154758973" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154758973">(Jan 09 2019 at 21:24)</a>:</h4>
<p>extremely agreed</p>



<a name="154759022"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154759022" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154759022">(Jan 09 2019 at 21:25)</a>:</h4>
<p>I saw the renaming in one of your later revisions</p>



<a name="154759146"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/154759146" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#154759146">(Jan 09 2019 at 21:27)</a>:</h4>
<p>if <a href="https://gist.github.com/nikomatsakis/6dd99a0126e3f82c64a6d4a6f9989c63#renaming-the-requires-relation-from-polonius" target="_blank" title="https://gist.github.com/nikomatsakis/6dd99a0126e3f82c64a6d4a6f9989c63#renaming-the-requires-relation-from-polonius">this</a> is still more or less what you want to do, I can do the renaming</p>



<a name="155197025"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/155197025" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#155197025">(Jan 15 2019 at 19:29)</a>:</h4>
<p>oh and I've had a lot of thoughts here. Will try to write some of them up this afternoon, I think, but the TL;DR is that I think my original post -- the one you started implememting, <span class="user-mention" data-user-id="116113">@lqd</span> -- will work out just fine, and the universe stuff we will handle as a separate step</p>



<a name="155197165"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/155197165" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#155197165">(Jan 15 2019 at 19:31)</a>:</h4>
<p>I'll go back to finish this soon after the other couple issues we talked about</p>



<a name="156399745"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/156399745" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#156399745">(Jan 18 2019 at 21:07)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> while I'm a bit stuck on the other issues, I've put up the <a href="https://github.com/rust-lang-nursery/polonius/pull/99" target="_blank" title="https://github.com/rust-lang-nursery/polonius/pull/99">PR for the missing subset errors </a> (and bors is still ignoring us  <span class="emoji emoji-1f602" title="joy">:joy:</span>)</p>



<a name="156615644"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/156615644" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#156615644">(Jan 22 2019 at 16:00)</a>:</h4>
<p><span class="user-mention" data-user-id="116113">@lqd</span> btw see my <a href="http://smallcultfollowing.com/babysteps/blog/2019/01/21/hereditary-harrop-region-constraints/" target="_blank" title="http://smallcultfollowing.com/babysteps/blog/2019/01/21/hereditary-harrop-region-constraints/">most recent blog post</a> for some discussion of the general direction I am looking at as a "next step"</p>



<a name="156615684"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/156615684" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#156615684">(Jan 22 2019 at 16:01)</a>:</h4>
<p>loving the title already :)</p>



<a name="156618923"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/156618923" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jake Goulding <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#156618923">(Jan 22 2019 at 16:42)</a>:</h4>
<p>Could have used a "harrumph"  in there.</p>



<a name="156624481"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/156624481" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#156624481">(Jan 22 2019 at 17:57)</a>:</h4>
<p>it's going to be fun/challenging if we have to reimplement Stephen Dolan's thesis :) (or just even understand it in my case hehe)</p>



<a name="156636658"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/156636658" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#156636658">(Jan 22 2019 at 20:30)</a>:</h4>
<p>;)</p>



<a name="156636746"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/polonius%2C%20universes%2C%20and%20subregions/near/156636746" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/polonius.2C.20universes.2C.20and.20subregions.html#156636746">(Jan 22 2019 at 20:30)</a>:</h4>
<p>I feel like I see a path forward, but I'm definitely open to finding better ways of doing things</p>



<hr><p>Last updated: Aug 07 2021 at 22:04 UTC</p>
</html>